Searching LC Catalog Using Derived Keys

The words that are input into the search term area of this search form will be used to derive a compression key search in the LC search system. If the user is familiar with LC compression key searching, actual compression keys can also be input into the search term area of the search form. However, if actual compression keys are input, the user must supply commas where necessary.

If one does not have a Library of Congress control number, ISBN, or ISSN available to use in searching, the most efficient means of searching for known author or title information (within the LC system) is through the use of compression key searches. The data included in the compression key search consists of groups of letters or numbers taken from the author and/or title information contained within the bibliographic or authority record compressed into a single, brief statement. In order to make effective use of such searches, it is necessary to know the names of the author(s) and/or precise title(s) for which you are searching.

There are three types of compression key searches:

• Title
• Personal Name
• Author and Title

Using one of the above compression key searches will retrieve as many records in the online catalog as contain a name or title which matches those included in the search term. One of the benefits of the compression key commands is that, when more than one record is retrieved using a compression key command, the records are displayed in alphabetical order according to the Library of Congress Filing Rules.

Title Key Guidelines

Supply the first four words of the title. If the title contains less than four words, supply the complete title. The Z39.50 target software will use these words to derive a compression key in the format (3,1,1,1). For example, the title Gone with the Wind would generate the following title compression key: gon,w,t,w

• Disregard articles when they appear as the first word of the title.
• Do not replace an ampersand (i.e., "&") with the word "and".
• When a title includes a numeral, use the numerals given.
• Special characters which look letters of the alphabet (e.g., Roman numerals) should be treated as the letters they resemble in constructing the search term.
• Disregard square brackets which appear within a title.
• The following characters function as word separators, dividing a single word or string of characters into two separate words: hyphen (i.e., "-"), forward slash (i.e., "/"), comma (i.e.,","), period (i.e., "."), colon (i.e., ":"), and parenthesis (i.e.,"(").
• The apostrophe and diacritical marks should not be included in the search term.
• Use English-language equivalents for "special" characters (e.g., use "ae" instead of "æ" and "o" instead og "ø").

Personal Name Key Guidelines

In constructing a search term for a personal name, it is necessary to first determine which part of the name is the entry element in the established heading. The format of the data included in the search term depends on whether the surname or the forename is the entry element. The Z39.50 target software will derive a compression key in the format (5,1) or (6) depending on whether a comma is present in the search term.

• If the surname is the entry element, one may enter the entire surname followed by a comma (comma is mandatory), followed by either the first letter of the forename or the entire forename.
• If the entry element is a forename or a family name alone, enter the name in direct order and do not use a comma.
• A space which occurs within the surname, forename, or family name must be retained.
• A hyphen which occurs within a name must be retained or replaced by a blank.
• Do not include apostrophes or diacritical marks.
• Use English-language equivalents for special characters (e.g., use "ae" instead of "æ" and "o" instead of "ø").

Author and Title Key Guidelines

The author and title search is used to search for an author/title combination.

• A comma must be used to separate the author portion of the search term from the title portion.
• Retain spaces or word separators (e.g., hyphen) that occur within the name.
• Do not include apostrophes or diacritical marks.
• Use English-language equivalents for special characters (e.g., use "ae" instead of "æ" and "o" instead of "ø").
• Follow above title search guidelines when constructing the title element of the search term.

Qualifiers

Qualifiers (either multiple field or single field) can be used with the derived key search term (following a semicolon) to limit the search to a single field or group of fields.

Key Search Term Examples (using qualifiers):

Title Searches

• netscape navigator 3.0;author=pfaffenberger
• chemistry;author=minnesota
• java;me=potts
• gone the the wind;260=macmillan;100=pratt

• ray,deborah;title=dummies 101
• stanek,william;650=html
• rey de castro,jose;sup=sucre
• ginsburg,mark;me=december

• potts,java;sbn=1883577772
• december,html;title=cgi
• ray,dummies;246=html
• rey de castro,recuerdos;name=jose

Multiple Field Qualifiers

• Author -- Main and added entries
• Name -- Personal names
• Title -- Bibliographic, uniform, and series titles
• Series -- Series statements and series added entries
• Subject -- Subject heading fields
• ME -- Main entry headings
• SE -- Series statements
• SU -- Subject heading fields
• AE -- Added entry fields
• SA -- Series added entry fields

Single Field Qualifiers

Numeric Tags

• 041 -- Language Code
• 043 -- Geographic Area Code
• 050 -- LC Call Number
• 082 -- Dewey Classification Number
• 086 -- Superintendent of Documents Number
• 100 -- Main Entry -- Personal Name
• 110 -- Main Entry -- Corporate Name
• 111 -- Main Entry -- Meeging or Conference Name
• 130 -- Main Entry -- Uniform Title Heading
• 240 -- Main Entry -- Uniform Title
• 245 -- Title
• 250 -- Edition
• 260 -- Imprint
• 400 -- See Reference -- Personal Name (Authority Records)
• 400 -- Series -- Personal Name
• 410 -- Series -- Corporate Name
• 411 -- Series -- Meeting or Confernece Name
• 440 -- Series -- Title
• 490 -- Series -- General
• 500 -- See Also Reference -- Personal Name (Authority Records)
• 510 -- See Also Reference -- Corporate Name (Authority Records)
• 550 -- See Also Reference -- Topical Heading (Authority Records)
• 500 -- General Note
• 600 -- Subject Added Entry -- Personal Name
• 610 -- Subject Added Entry -- Corporate Name
• 611 -- Subject Added Entry -- Meeting or Conference Name
• 630 -- Subject Added Entry -- Uniform Title Heading
• 650 -- Subject Added Entry -- Topical Heading
• 651 -- Subject Added Entry -- Geographic Heading
• 700 -- Added Entry -- Personal Name
• 710 -- Added Entry -- Corporate Name
• 711 -- Added Entry -- Meeting or Confence Name
• 730 -- Added Entry -- Uniform Title Heading
• 800 -- Series Added Entry -- Personal Name
• 810 -- Series Added Entry -- Corporate Name
• 811 -- Series Added Entry -- Meeting or Conference Name
• 840 -- Series Added Entry -- Title

Mnemonic Tags

• CRD -- LCCN
• SBD -- ISBN
• GAC -- Geographic Area Code
• CAL -- LC Call Number
• DDC -- Dewey Classification Number
• SDC -- Superintendent of Documents Number
• MEP -- Main Entry -- Personal Name
• MEC -- Main Entry -- Corporate Name
• MEM -- Main Entry -- Meeting or Conference Name
• MEU -- Main Entry -- Uniform Title Heading
• ROM -- Romanized Title
• TIL -- Title
• UIT -- Uniform Title
• EDN -- Edition
• IMP -- Imprint
• COL -- Collation (Extent of Item -- Physical Description)
• SEP -- Series -- Personal Name
• SEC -- Series -- Corporate Name
• SEM -- Series -- Meeting or Conference Name
• SET -- Series -- Title
• SER -- Series -- General
• SUP -- Subject Added Entry -- Personal Name
• SUC -- Subject Added Entry -- Corporate Name
• SUM -- Subject Added Entry -- Meeting or Conference Name
• SUT -- Subject Added Entry -- Topical Heading
• SUG -- Subject Added Entry -- Geographic Heading
• AEP -- Added Entry -- Personal Name
• AEC -- Added Entry -- Corporate Name
• AEM -- Added Entry -- Meeting or Conference Name
• AEU -- Added Entry -- Uniform Title Heading
• AED -- Added Entry -- Title Traced Differently
• SAP -- Series Added Entry -- Personal Name
• SAC -- Series Added Entry -- Corporate Name
• SAM -- Series Added Entry -- Meeting or Conference Name
• SAT -- Series Added Entry -- Title

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